When grinding the crankshaft crank, in order to ensure the offset L, we designed a simple and easy-to-use fixture that can guarantee L within ±0.020mm (see figure). The tray of the V-shaped groove body 2 is matched with the main shaft of the grinding machine, and the size and position of the V-shaped groove are determined according to the crank eccentricity L, and the west side of the V-shaped groove must be parallel to the center line. Loading the workpiece into the fixture during use,